Operation Pallial, the investigation launched amid claims of historic sexual abuse at North Wales care homes, has so far identified 37 people who are being investigated as suspects.

The National Crime Agency (NCA) launched the operation in 2012, and so far, one person has been charged with a large number of serious sexual offences.

Senior Investigating Officer Ian Mulcahey said the number of people coming forward to report historical allegations continues to increase with a total of 255 people having reported one or more allegations up until February 8 last week.

Mr Mulcahey said: “Information given to us by 212 people is under active investigation at this time and has resulted in 37 people being identified as potential suspects.

“Of these, 19 suspects have been arrested and interviewed, three more have voluntarily attended police stations for interview under caution and 12 are believed to have died. Efforts to locate three others, one of whom may be abroad, are ongoing. To date, the CPS has charged one person with a large number of sexual offences.”

Operation Pallial has had over 120 names or partial details of individuals suspected of being responsible for physical or sexual abuse and police are trying to find them.

Mr Mulcahey said: “There are, potentially, 61 repeat offenders within this number, of whom around 17 may be deceased, but this information requires further investigation for the information to be confirmed or excluded.”

Operation Pallial launched in November 2012 at the request of North Wales Police chief constable Mark Polin has a team of 26 officers based at the NCA’s North West Hub near Warrington. It is being supported by colleagues in social services and charities.

In 2000, the Waterhouse Inquiry was launched to study allegations in the former council areas of Gwynedd and Clwyd since 1974.

Eight people were prosecuted, seven of whom were convicted.

Mr Mulcahey said: “It is reassuring to know that individuals have had the confidence to come forward and we will fully investigate all information they are able to provide. In cases where people have contacted us but have declined to support further enquiries we will still ensure they receive any advice and support they need.”

Offences under investigation are believed to have been committed between 1953 and 1995 on boys, girls and young adults aged between six and 19 years old. A total of 28 care homes in North Wales are currently being investigated

The National Crime Agency-led investigation is supported by officers and staff from police forces across England, particularly north west of England.

The cost of phase two of the investigation, which is being met by the Home Office to avoid any impact on local policing in North Wales, is currently £727,000 (May 2013 – November 2013).

The investigation has already been independently reviewed to ensure that it remains “focused” on the victims and efficient.”